Quiksilver, Inc. (ZQK) is an outdoor sports lifestyle company that designs, produces and distributes a diversified mix of branded apparel, footwear, accessories, snowboards and related products. ZQK also gets F’s in Earnings Momentum, Analyst Earnings Revisions, Equity and Sales Growth. Since January 1, ZQK has fallen 25.6%. This is worse than the S&P 500, which has remained flat. For more information, get Portfolio Grader’s complete analysis of ZQK stock.

Rubicon Technology, Inc. (RBCN) is an electronic materials provider that develops, manufactures and sells monocrystalline sapphire and other innovative crystalline products for LEDs, RFICs, blue laser diodes, optoelectronics and other optical applications. RBCN gets F’s in Earnings Momentum, Analyst Earnings Revisions, Equity and Sales Growth as well. The price of RBCN is down 23.1% since the first of the year. For more information, get Portfolio Grader’s complete analysis of RBCN stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.